The present invention generally relates to a filling machine for filling containers with contents. More particularly, the present invention pertains to a flushing device of a filling machine for filling containers with liquid food products.
One version of a packaging filling machine which fills liquid food products, such as milk and juice, into a container to produce a filled packaging container involves using a web-shaped packaging material on a reel. The web-shaped packaging material on the reel is charged to a charging station of the filling machine and is then let out from the charging station and conveyed to the filling machine.
The packaging material consists of a flexible laminate, which can include a paper substrate and plastic layers of polyethylene laminated on both sides of the paper substrate. If necessary, a barrier layer, that can include aluminum foil and a resin having gas barrier properties, is formed between the paper substrate and the plastic layers.
Upon being let out from the charging station, the packaging material is longitudinally sealed in the lengthwise direction and formed into a tubular shape. The tubular packaging material is then transversely pressed from opposite sides by a seal and cutting mechanism. This seal and cutting mechanism can include an induction heater as the seal device and a cutter as the cutting device. The packaging material is sealed in the transverse direction at successive fixed intervals by the seal device. At this time, a pair of forming flaps surrounds and presses the tubular packaging material from the outside, and transforms the packaging material into a pillow-shape.
At once, using the cutting device, the pillow-shaped packaging material is cut along the centerline of the transverse seal produced by the seal device. As a result, plural pillow-shaped preformed containers containing a liquid food product are formed, with the preformed containers then being formed into a brick-shaped packaging container through operation of a final folder.
In connection with the transverse sealing mentioned above, liquid food is filled into the tubular packaging material. In the position below the level of the filled liquid food product, the packaging material is pressed from both sides by the sealing device, is heated and is thus transverse-sealed.
Much of the liquid food product is squeezed out from the transverse seal zone. However, some of the liquid food may remain along the centerline in this transverse seal zone. Because the seal zone is cut with the cutting device, the cutting device tends to become stained or soiled by the liquid food product. The liquid food product can also stain or soil the cut portion of the packaging container. Published International Application No. WO98/09870 proposes a machine for cleaning the cutting device with cleaning water. In this machine, cleaning medium, for example water, is directly jetted out at the tip of the cutting device or the cutter knife.
In light of the foregoing, a need exists for avoiding the disadvantages and drawbacks discussed above.
A need thus exists for a way of cleaning the peripheral surface of the packaging material.
A need also exists for a way of cleaning the sealing device and the cutting device, while also sterilizing them.
It would be desirable to achieve the foregoing in a way that also imparts lubricity to the outside of the packaging material, thus facilitating smooth movement of the packaging material and improved packaging formation.
According to one aspect of the invention, a filling machine for producing containers containing liquid food product includes a series of rollers for forming a web-shaped packaging material into a tubular packaging material, a filling tube for introducing a liquid food product into the tubular packaging material while the tubular packaging material is being conveyed downwardly, a heat sealing bar providing with a heating mechanism and engageable with a cutting bar to produce a seal area forming a transverse seal across the tubular packaging material below a level of the liquid food product, and a cutter provided on the cutting bar to cut the tubular packaging material in the seal zone to form a preformed container containing the liquid food product. At least one nozzle is positioned to direct a sterilizing flushing liquid towards the outside surface of the tubular packaging material.
In accordance with another aspect of the invention, a filling machine for producing containers containing liquid food product includes a filling device for filling a liquid food product into a tubular packaging material conveyed downwardly from above, a sealing mechanism for sealing the tubular packaging material transversely under a liquid level of the liquid food product in the tubular packaging material to form a transverse seal zone, a cutting mechanism for cutting the seal zone to form a preformed container containing liquid food product, and a flushing liquid supplying arrangement for supplying a flushing liquid containing a disinfectant towards an outside surface of the packaging material.
According to another aspect of the invention, a method for producing containers containing liquid food product involves forming a web-shaped packaging material into a tubular packaging material, introducing a liquid food product into the tubular packaging material while the tubular packaging material is being conveyed downwardly, forming a transverse seal across the tubular packaging material containing the liquid food product, cutting the tubular packaging material in the transverse seal of the packaging material to form a filled preformed container, directing sterilizing flushing liquid towards the tubular packaging material while the tubular packaging material is being cut in the transverse seal of the packaging material.
By virtue of the present invention, the flushing liquid cleans and sterilizes the outer surface of the tubular packaging material, and is able to flow downwardly to wash and sterilize the sealing bar and the cutter. Also, the flushing liquid can cool the packaging material after the formation of the transverse seal and so the plastic or resin material of the packaging material is relatively rapidly hardened. It is thus less likely that the plastic or resin material will be stained or soiled. As a result, the appearance of the packaging material is improved.